Lithium battery real-time sorting method, device, equipment and storage medium

Abstract

Lithium battery real-time sorting method, device, equipment and storage medium, fully discharge several batteries to be sorted, divide the SOC interval of each battery into N intervals; After charging, online measurement is performed to obtain N dynamic impedance test values; based on the equivalent circuit model of battery dynamic impedance, according to the N dynamic impedance test values, the charge transfer resistance of the kth SOC interval and the representation of the kth SOC interval are obtained. The correlation coefficient ρ of the characteristic parameters of the Warburg diffusion impedance value; the batteries within the range of ρ±Δλ are regarded as the same type of batteries, and Δλ is the preset error, so as to complete the online real-time sorting of batteries. The battery sorting method adopted in the present invention can test the impedance of the battery online and extract the characteristic parameters of the battery without damaging the battery or affecting the operation of the battery, thereby realizing the online real-time sorting of the battery.

Description

technical field [0001] The invention belongs to the technical field of battery sorting, and relates to a real-time sorting method, device, equipment and storage medium for lithium batteries. Background technique [0002] Since the energy storage technology of single lithium-ion batteries has not reached the level of large capacity and super power, large-scale energy storage requires thousands of single lithium-ion batteries in series and parallel to form a battery pack to work. The system often includes multiple battery packs, and the battery pack includes multiple battery cells. With the long-term charge-discharge cycle of the energy storage system, various parameters of the single battery will change, including the state of charge, internal resistance and available capacity, etc. The differences in these parameters between the single batteries will This leads to the phenomenon of overcharge and overdischarge of some single cells during the charging and discharging process...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to propose a real-time sorting method, device, equipment and storage medium for lithium batteries based on the dynamic impedance of the battery, using the dynamic impedance of the battery as the basis for sorting the battery, and the dynamic impedance is based on the lithium ion battery generated during charging and discharging. The phenomenon of electrode polarization is different from the static impedance in which the electrode maintains a balanced potential in a static state, and overcomes the problem that the static impedance cannot accurately reflect the polarization of the battery due to charging and discharging.

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